Inventors Race to File Patents

Inventors are rushing to file patent applications ahead of a change in the U.S. patent system that is likely to make it more expensive and difficult to win protection for new ideas.

The federal Patent & Trademark Office received 12,670 patent applications in the week ended March 2, its latest available data. The tally was the highest weekly total of the year and the second-highest weekly total of the past five months. Tallies...